Autoimmune Disease Definition, Causes, and Treatments

doctor talking with patient about autoimmune disease
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Autoimmune disease develops when your body's immune system mistakenly starts to attack your own cells, damaging them and causing symptoms. Common autoimmune diseases include celiac disease, rheumatoid arthritis, multiple sclerosis and type 1 diabetes.

Normally, your body's immune system manufactures molecules called antibodies that are designed to fight invaders such as viruses that can make you sick.

 But sometimes that system goes awry, and your body creates so-called autoantibodies that attack your own cells, rather than those foreign invaders.

This attack from your own immune system can cause symptoms and damage to your bodily systems. "Auto" means "self" in Latin — that's where we get the term "autoimmune disease."

Common Autoimmune Diseases

Nearly every body part can be affected by autoimmune disease, from your skin to your heart and brain. In fact, there are more than 80 autoimmune diseases recognized by medical science. Here are some of them:

  • Celiac disease affects nearly one in every 100 Americans. When you have celiac, eating something that contains the protein gluten (found in wheat, barley, and rye) triggers your immune system to attack the lining of your small intestine.
  • Rheumatoid arthritis is recognized as the most common autoimmune disease in the U.S. Some 3.6% of women and 1.7% of men will be diagnosed with rheumatoid arthritis in their lifetimes. In rheumatoid arthritis, the autoimmune disease attacks your joints and sometimes your organs.
  • Type 1 diabetes occurs when your immune system attacks and destroys the cells in your pancreas that make insulin, which is needed for you to process sugar. Type 1 diabetes usually occurs early in life, unlike type 2 diabetes, which is not an autoimmune condition and which generally occurs later in life. It's common for people with type 1 diabetes to also be diagnosed with celiac disease.

Other autoimmune conditions include autoimmune hepatitis, alopecia areata (autoimmune hair loss), and psoriasis.


The causes are not clear. Your genes can predispose you to autoimmune diseases (there's a strong genetic link in celiac disease, for example), but many people with the "right" genes never develop the illness. So there must be something else involved, too.

Some scientists speculate that we as a society have actually become too clean and that our immune systems are confused and start attacking our own bodily systems as a result. It's also possible that external influences such as microorganisms or even medications could trigger some autoimmune diseases.

It's not uncommon for people to have more than one autoimmune disease — for example, a recent study from Turkey found one-third of a group of celiacs had at least one additional autoimmune condition.

So there may be common genes or risk factors.


Although autoimmune diseases share a common element in that they all involve an attack by your immune system on your own cells, there's no one treatment that works for all of them.

In the case of celiac disease, treatment involves the gluten-free diet — once most people with celiac disease stop consuming gluten, their conditions go into remission and their intestinal damage begins to heal. Type 1 diabetics must take insulin to manage their condition, and those with autoimmune thyroid disease generally must take replacement thyroid hormones.

Treatments for other autoimmune diseases may involve medicines that try to calm your immune system. Your doctor also may recommend certain nutritional supplements to help correct any deficiencies, or may refer you for physical therapy if your ability to move easily is affected.


Autoimmune Disorders. U.S. Library of Medicine fact sheet. Accessed October 13, 2015.

Crowson CS et al. The Lifetime Risk of Adult-Onset Rheumatoid Arthritis and Other Inflammatory Autoimmune Rheumatic Diseases. Arthritis and Rheumatism. 2011 Mar;63(3):633-9.

Demirezer Bolat A et al. Risk Factors for Polyautoimmunity among Patients with Celiac Disease: A Cross-Sectional Survey. Digestion. 2015 Sep 17;92(4):185-191.